JP5469305B2 - Bonding material, manufacturing method thereof, and honeycomb structure using the same - Google Patents

Description

  The present invention relates to a ceramic structure for bonding a plurality of ceramic members, and more particularly to a bonding material used for a honeycomb structure for integrally bonding a plurality of honeycomb segments.

  The honeycomb structure as a collection filter for exhaust gas, for example, as a diesel particulate filter (DPF) for capturing and removing particulate matter (particulates) contained in exhaust gas from a diesel engine or the like It is incorporated in the exhaust system of diesel engines.

  Such a honeycomb structure is disposed so that a plurality of cells that are partitioned and formed by porous partition walls made of, for example, silicon carbide (SiC) are parallel to each other in the central axis direction. Have a structure. Moreover, the edge part of the adjacent cell is plugged alternately (in a checkered pattern). That is, one cell is open at one end and the other end is sealed, and another cell adjacent thereto is sealed at one end and the other end is open. doing.

  By adopting such a structure, the exhaust gas flowing into a predetermined cell (inflow cell) from one end is passed through a cell (outflow cell) adjacent to the inflow cell by passing through a porous partition wall. When the particulate matter (particulates) in the exhaust gas is captured by the partition wall when it is allowed to flow out and pass through the partition wall, the exhaust gas can be purified.

  In order to continuously use such a honeycomb structure (filter) for a long period of time, it is necessary to regenerate the filter. That is, in order to remove the increase in pressure loss due to the particulates accumulated with time in the filter, it is necessary to burn and remove the particulates accumulated in the filter. When the filter is regenerated, a large thermal stress is generated, and this thermal stress causes a defect such as a crack or breakage in the honeycomb structure. In response to such a demand for improvement in thermal shock resistance against thermal stress, a honeycomb having a divided structure having a function of dispersing and relaxing thermal stress by integrally bonding a plurality of honeycomb segments with a bonding material layer. A structure has been proposed, and its thermal shock resistance can be improved to some extent. Each of the honeycomb structures having such a divided structure has a shape that constitutes a part of the entire structure, and a shape that constitutes the entire structure by being assembled in a direction perpendicular to the central axis. A plurality of honeycomb segments are integrally bonded by a bonding material layer, and the entire cross-sectional shape cut by a plane perpendicular to the central axis is formed into a predetermined shape such as a circle, and then the outer periphery thereof. The surface is covered with a coating material.

  However, in recent years, the demand for larger filters has increased, and the thermal stress generated during regeneration has also increased. In order to prevent the above-described defects, it is strongly desired to improve the thermal shock resistance of the structure. became. In particular, a bonding material layer for integrally bonding a plurality of honeycomb segments is desired to realize a honeycomb structure excellent in thermal shock resistance by realizing an excellent stress relaxation function and bonding strength. ing.

  In response to these problems, the addition of inorganic fibers and organic binders to the sealing material (bonding material layer) suppresses the occurrence of migration during the drying and curing process and suppresses the occurrence of the aforementioned defects. Thus, a ceramic structure (honeycomb structure) intended to improve durability has been disclosed (see Patent Document 1).

  Also, a honeycomb structure that satisfies either the Young's modulus of the bonding layer material between the honeycomb segments is 20% or less of the honeycomb segment material, or the material strength of the bonding layer is smaller than the material strength of the honeycomb segment (low Young (Use of rate bonding material) is disclosed (see Patent Document 2).

  However, in the sealing material (bonding material layer) used in the ceramic structure (honeycomb structure) disclosed in Patent Document 1, in the uniform structure realized by the entanglement of the inorganic fibers and the organic binder, There has been a problem that it is difficult to ensure both the bonding strength at the segment / bonding material layer interface and the stress relaxation function of the bonding material layer itself.

  Further, the lower Young's modulus of the bonding material forming the bonding layer disclosed in Patent Document 2 is effective in reducing thermal stress and thermal deformation generated between the honeycomb segments. In addition, when the porosity of the bonding material is increased, the bonding strength between the honeycomb segments becomes insufficient, and a sound bonded honeycomb segment assembly cannot be obtained.

Japanese Patent No. 3121497 JP 2001-190916 A

  The present invention has been made in view of the above-described problems of the prior art, and the object thereof is to form a bonding layer having a high Young's modulus and to achieve low expansion, and thus occurs. An exhaust gas collection filter that can suppress deformation of honeycomb segments due to thermal stress at the bonding layer and reduce the occurrence of defects such as cracks, especially particulate matter (particulates) in diesel engine exhaust gas It is to provide a bonding material that can be suitably used during the production of a diesel particulate filter (DPF) that collects the like.

  In order to achieve the above object, according to the present invention, the following bonding material, a manufacturing method thereof, and a honeycomb structure using the same are provided.

[1] Mainly from two or more kinds of fillers and matrices of a filler (1) having an average linear thermal expansion coefficient at 25 to 800 ° C. of 50% or less of the article to be joined and a filler (2) having a Young's modulus of 100 GPa or more. The Young's modulus after curing is 20% or more of the object to be bonded, and the average linear thermal expansion coefficient at 25 to 800 ° C. after curing is 0.1 × 10 ⁻⁶ to 2.0 × 10 ⁻⁶ · K ⁻¹ and 70% or less of the object to be bonded, and the material of the object to be bonded is silicon carbide (SiC), silicon carbide (SiC) as an aggregate, and silicon (Si ) silicon is formed as the bonding material to - silicon carbide based composite material, silicofluoride-containing - is composed of at least one selected from silicon carbide composite material or Ranaru group, the filler (1) and said filler (2) before and the volume fraction of the total sum Equal to the volume fraction of the matrix, the volume fraction of filler in total of said filler (1) and the filler (2) (1): filler (2) = 5 0: 50-9 0: is 10, the filler (1), a Kojerai bets, the filler (2) is silicon carbide, nitride boron, and talc, mica, and at least one or more selected from the group consisting of glass flakes, and the plate At least one selected from the group consisting of boron nitride, talc, mica, and glass flakes that are shaped particles, and the matrix is colloidal silica, colloidal alumina, ethyl silicate, water glass, silica polymer, aluminum phosphate, A joining material that is at least one selected from the group consisting of bentonite.

[ 2 ] The bonding material according to [1 ], wherein the filler (1) has an average linear thermal expansion coefficient at 25 to 800 ° C. of 2.5 × 10 ⁻⁶ · K ⁻¹ or less.

[ 3 ] The bonding material according to [1] or [ 2], wherein the matrix is colloidal silica.

[ 4 ] The bonding material according to any one of [1] to [ 3 ], which is used for bonding honeycomb segments.

[ 5 ] A method for producing a bonding material for obtaining the bonding material according to any one of [1] to [ 4 ], wherein the filler (1), the filler (2), and the matrix are mixed. The manufacturing method of a joining material including the process of obtaining a paste-like joining material composition by kneading | mixing.

[ 6 ] A ceramic structure produced by bonding a plurality of ceramic members with the bonding material according to any one of [1] to [ 4 ].

[7] above [1] to the bonding material according to any one of [4], the honeycomb structure manufactured by bonding a plurality of honeycomb segments.

1 is a perspective view schematically showing an embodiment of a honeycomb structure of the present invention (the entire cross-sectional shape cut by a plane perpendicular to the central axis is circular). It is the front view which looked at a part of other embodiment (the whole cross-sectional shape cut | disconnected by the plane perpendicular | vertical with respect to a center axis | shaft is square) of the honeycomb structure of this invention from the end surface side. FIG. 6 is a perspective view schematically showing a honeycomb segment used in another embodiment of the honeycomb structure of the present invention. It is the sectional view on the AA line in FIG.

Explanation of symbols

1: honeycomb structure, 2: honeycomb segment, 4: coating material, 5: cell, 6: partition wall, 7: filler, 9: bonding material layer, 10: honeycomb segment bonded body.

  Hereinafter, the bonding material of the present invention will be described in detail on the basis of specific embodiments. However, the present invention is not construed as being limited thereto, and those skilled in the art do not depart from the scope of the present invention. Various changes, modifications and improvements can be made based on the knowledge.

  In the bonded material according to the present invention, in a bonded body in which two or more objects to be bonded are integrated via a bonding material layer, the Young's modulus of the bonding material layer is 20% or more of the object to be bonded (more preferably 25% or more and 200% or less) and the average linear thermal expansion coefficient is 70% or less (more preferably 1% or more and 65% or less) of the object to be joined.

  As a result, the bonding material of the present invention relieves thermal stress and thermal deformation generated between the honeycomb segments as compared with a conventional bonding material (for example, see Patent Document 2), such as lower Young's modulus. In contrast to this, the new Young's modulus is increased to suppress the thermal stress and thermal deformation generated between the honeycomb segments and to ensure sufficient bonding strength between the honeycomb segments. A joined body can be obtained, which can contribute to improvement of productivity and quality of the honeycomb structure.

The bonding material of the present invention has an average linear thermal expansion coefficient of 3 × 10 ⁻⁶ · K ⁻¹ or less (more preferably 2.5 × 10 ⁻⁶ · K ⁻¹ or less, and ^still more preferably 0.1. ^{X10 −6} · K ⁻¹ or more and 2.0 × 10 ⁻⁶ · K ⁻¹ or less). This is because the smaller the thermal expansion coefficient of the bonding material, the easier it is to suppress thermal stress and thermal deformation that occur between the honeycomb segments.

  The bonding material of the present invention is obtained by curing a bonding material composition containing a filler and a matrix as main components and containing an additive such as an organic binder and water. The proportion of the filler in the bonding material composition is preferably 10 to 95% by volume (more preferably 20 to 90% by volume), and the proportion of the matrix is 5 to 90% by volume (more preferably 10%). ~ 80% by volume).

  Furthermore, the bonding material of the present invention comprises a filler having an average linear thermal expansion coefficient of 50% or less of that to be bonded (hereinafter referred to as filler (1)) and a filler having a Young's modulus of 100 GPa or more (hereinafter referred to as filler (2). May be obtained from a bonding material composition mainly composed of two or more fillers and a matrix.

  At this time, the volume fraction of the filler in the bonding material composition from which the bonding material of the present invention is obtained is filler (1): filler (2) = 5: 95 to 95: 5 (more preferably 10:90 to 90:10).

  Further, the bonding material of the present invention is mainly composed of a filler (hereinafter referred to as filler (3)) having an average linear thermal expansion coefficient of 50% or less of an object to be bonded and a Young's modulus of 100 GPa or more and a matrix. It is preferable to be obtained from the obtained bonding material composition.

At this time, as for the joining material of this invention, the average linear thermal expansion coefficient of a filler (1) and a filler (3) is 2.5 * 10 <^-6> * K- ¹ or less (more preferably, 2.0 * 10 < ^- >). ⁶ × K ⁻¹ or less, more preferably 0.01 × 10 ⁻⁶ · K ⁻¹ or more and 1.5 × 10 ⁻⁶ · K ⁻¹ or less). This is because the characteristic of the material (filler and matrix) constituting the bonding material is reflected in the characteristic of the bonding material, so that the average linear thermal expansion coefficient of the bonding material is 3 × 10 ⁻⁶ · K ⁻¹ or less. This is because the average linear thermal expansion coefficient of the filler needs to be a value slightly lower than that of 2.5 × 10 ⁻⁶ · K ⁻¹ or less.

  Here, the filler (1) used in the present invention is at least one selected from the group consisting of cordierite, β-spodumene, amorphous silica, aluminum titanate, and zirconium phosphate (more preferably, 1 It is preferable to be about ~ 2 types).

The filler (2) used in the present invention is silicon carbide, alumina, quartz, aluminum nitride, B ₄ C, mullite, SiAlON, silicon nitride, zirconia, cordierite, aluminum titanate, zirconium phosphate, boron nitride, talc. , Mica, and at least one selected from the group consisting of glass flakes. In particular, the filler (2) used in the present invention contains plate-like particles such as boron nitride, talc, mica, and glass flakes, so that it is mechanical in the bonding material (bonding material composition after curing) of the present invention. Characteristics can be improved.

Furthermore, the filler (3) used in the present invention is preferably at least one selected from the group consisting of cordierite, aluminum titanate, and zirconium phosphate.
Therefore, specifically, the bonding material composition constituting the bonding material of the present invention is at least selected from the group consisting of cordierite, β-spodumene, amorphous silica, aluminum titanate, and zirconium phosphate. One or more fillers and silicon carbide, alumina, quartz, aluminum nitride, B ₄ C, mullite, SiAlON, silicon nitride, zirconia, cordierite, aluminum titanate, zirconium phosphate, boron nitride, talc, mica, and glass Two or more fillers with at least one filler selected from the group consisting of flakes, and a matrix, or at least selected from the group consisting of cordierite, aluminum titanate, and zirconium phosphate One or more fillers and matrix It preferably contains a scan.

  The shape of the fillers (1) to (3) used in the present invention is not particularly limited in any shape such as a spherical shape, a plate shape, an irregular shape such as a crushed material, a fibrous shape, a needle shape, or the like. From the viewpoint of cost, it is preferably an irregular shape such as a crushed material, and from the viewpoint of the strength of the bonding material after curing, it is preferably a shape having a high aspect ratio such as a plate shape, needle shape, fiber shape, A plate shape is more preferable from the viewpoint of health. Furthermore, the average particle size of the fillers (1) to (3) used in the present invention is preferably 0.01 μm or more and 100 μm or less, and even when the particle size distribution is a normal distribution, two or more normal distributions are present. It may be an existing distribution.

  The matrix used in the present invention is preferably an inorganic adhesive because it is necessary to appropriately bond filler particles to each other and between an object to be bonded and a filler. Colloidal silica, colloidal alumina, ethyl silicate, water glass, silica polymer Examples thereof include aluminum phosphate and bentonite, but colloidal silica is particularly preferable. This is because it has excellent adhesive strength, ease of compatibility with fillers, chemical stability, heat resistance, and the like.

  Next, in the method for producing a bonding material of the present invention, the filler (1) and the filler (2), or the filler (3) are mixed, and an organic binder (for example, methyl cellulose (MC), carboxymethyl cellulose, depending on the case. (CMC) etc.), a foamed resin and a dispersing agent are added, and further, an inorganic adhesive (for example, colloidal silica) as a matrix, and optionally water are mixed and kneaded for a predetermined time in a mixer. Thus, a paste-like bonding material composition can be produced.

  Further, when the objects to be bonded are bonded to each other using the bonding material of the present invention, the bonding temperature with the objects to be bonded is 1000 ° C. or lower (more preferably, 50 ° C. or higher and 900 ° C. or lower, more preferably 100 ° C. or higher and 800 ° C. (Degrees C or less) is desirable from the viewpoint that sufficient strength and bonding state can be expressed. Even if the temperature exceeds 1000 ° C., bonding can be performed without any problem, but it is not preferable because desired characteristics (such as Young's modulus and thermal expansion coefficient) are hardly obtained.

Next, an example of the structure of the honeycomb structure to which the bonding material of the present invention is applied will be specifically described.
As shown in FIG. 1 and FIG. 2, the honeycomb structure 1 of the present invention has a plurality of cells 5 that are partitioned and formed by porous partition walls 6 and are formed in the direction of the central axis of the honeycomb structure 1. The structure is arranged so as to be parallel to each other, each has a shape constituting a part of the whole structure, and the whole structure is assembled by being assembled in a direction perpendicular to the central axis of the honeycomb structure 1. A plurality of honeycomb segments 2 having a shape to be configured are configured as a honeycomb segment bonded body 10 integrally bonded by a bonding material layer 9 formed from the bonding material of the present invention.

  Here, after the bonding of the honeycomb segments 2 by the bonding material layer 9, the overall cross-sectional shape cut along a plane perpendicular to the central axis of the honeycomb structure 1 is circular, elliptical, triangular, square, and other shapes. The outer peripheral surface is covered with the coating material 4. When this honeycomb structure 1 is used as a DPF, particulate matter (particulates) containing soot discharged from the diesel engine can be captured by disposing the honeycomb structure 1 in an exhaust system or the like of the diesel engine.

  In FIG. 1, the cells 5 and the partition walls 6 are shown only in one honeycomb segment 2. As shown in FIGS. 3 and 4, each honeycomb segment 2 has a shape constituting a part of the entire structure of the honeycomb structure 1 (honeycomb segment bonded body 10) (see FIG. 1). It has a shape that constitutes the entire structure by being assembled in a direction perpendicular to the central axis (see FIG. 1). The cells 5 are arranged so as to be parallel to each other in the central axis direction of the honeycomb structure 1, and the respective end portions of the adjacent cells 5 are alternately sealed with the fillers 7.

  In the predetermined cell 5 (inflow cell), the left end side in FIGS. 3 and 4 is open, while the right end side is sealed with the filler 7, and another cell 5 (outflow cell) adjacent thereto is sealed. In FIG. 2, the left end side is sealed with the filler 7, but the right end side is open. By such sealing, as shown in FIG. 2, the end face of the honeycomb segment 2 has a checkered pattern. When the honeycomb structure 1 to which such a plurality of honeycomb segments 2 are joined is disposed in the exhaust gas exhaust system, the exhaust gas flows into the cells 5 of the honeycomb segments 2 from the left side in FIG. 4 and moves to the right side. .

  FIG. 4 shows a case where the left side of the honeycomb segment 2 serves as an exhaust gas inlet, and the exhaust gas flows into the honeycomb segment 2 from the open cells 5 (inflow cells) without being sealed. The exhaust gas flowing into the cell 5 (inflow cell) passes through the porous partition wall 6 and flows out from the other cell 5 (outflow cell). When passing through the partition walls 6, particulate matter (particulates) containing soot in the exhaust gas is captured by the partition walls 6. In this way, exhaust gas can be purified. By such trapping, particulate matter containing particulates (particulates) containing soot accumulates with time in the honeycomb segment 2 and the pressure loss increases, so regeneration that soot is burned is performed. 2 to 4 show the honeycomb segment 2 having a square cross section as a whole, it may be triangular, hexagonal or the like. The cross-sectional shape of the cell 5 may also be a triangle, a hexagon, a circle, an ellipse, or other shapes.

  As shown in FIG. 2, the bonding material layer 9 is formed from the bonding material of the present invention, and is applied to the outer peripheral surface of the honeycomb segment 2 to function to bond the honeycomb segment 2. The bonding material layer 9 may be applied to the outer peripheral surfaces of the adjacent honeycomb segments 2, but only between one of the corresponding outer peripheral surfaces between the adjacent honeycomb segments 2. Also good. Such application to only one side of the corresponding surface is preferable in that the amount of the bonding material layer 9 used can be saved. The thickness of the bonding material layer 9 is determined in consideration of the bonding force between the honeycomb segments 2 and is appropriately selected within a range of 0.5 to 3.0 mm, for example.

  As a material of the honeycomb segment 2 used in the present embodiment, silicon carbide (SiC), silicon carbide (SiC) is used as an aggregate, and silicon (Si) is used as a binder from the viewpoint of strength and heat resistance. Silicon-silicon carbide composite material, silicon nitride, cordierite, mullite, alumina, spinel, silicon carbide-cordierite composite material, silicon-silicon carbide composite material, lithium aluminum silicate, aluminum titanate, Fe-Cr-Al system The thing comprised from at least 1 type selected from the group which consists of metals can be mentioned. Among these, those made of silicon carbide (SiC) or a silicon-silicon carbide based composite material are preferable.

  For example, the honeycomb segment 2 is prepared by adding a binder such as methyl cellulose, hydroxypropoxyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, and polyvinyl alcohol, a surfactant, water as a solvent, and the like to those appropriately selected from the above materials. Thus, it is possible to obtain a plastic clay, extrude the clay so as to have the above-mentioned shape, and then dry it with microwaves, hot air or the like and then sinter.

  As the filler 7 used for plugging the cells 5, the same material as that of the honeycomb segment 2 can be used. Sealing with the filler 7 is performed by filling the open cells 5 by immersing the end faces of the honeycomb segments 2 in the slurry-like filler 7 in a state where the cells 5 that are not sealed are masked. Can do. The filling of the filler 7 may be performed before or after firing after the formation of the honeycomb segment 2, but it is preferable to perform the filling before firing because the firing process is completed once.

  After manufacturing the honeycomb segment 2 as described above, a paste-like bonding material composition is applied to the outer peripheral surface of the honeycomb segment 2 to form a bonding material layer 9, and a predetermined three-dimensional shape (the entire structure of the honeycomb structure 1) is formed. ), A plurality of honeycomb segments 2 are assembled so as to be pressure-bonded in this assembled state, and then dried by heating. In this manner, a joined body in which the plurality of honeycomb segments 2 are integrally joined is manufactured. Thereafter, the joined body is ground into the above-described shape, and the outer peripheral surface is covered with the coating material 4 and heated and dried. In this way, the honeycomb structure 1 shown in FIG. 1 is manufactured. As the material of the coating material 4, the same material as the bonding material layer 9 can be used. The thickness of the coating material 4 is appropriately selected within a range of 0.1 to 5 mm, for example.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.

( Reference Example 1)
(Manufacture of honeycomb segments)
As a honeycomb segment raw material, SiC powder and metal Si powder were mixed at a mass ratio of 80:20, and a pore former, an organic binder, a surfactant and water were added thereto to produce a plastic clay. This kneaded material is extruded and dried, and the partition wall thickness is 310 μm, the cell density is about 46.5 cells / cm ² (300 cells / square inch), the cross section is a regular square with a side of 35 mm, and the length is 152 mm. A honeycomb segment formed body was obtained. In this honeycomb segment molded body, both end faces of the cells were sealed so that the end faces had a checkered pattern. That is, the sealing was performed so that adjacent cells were sealed at opposite ends. As the plugging material, the same material as the honeycomb segment material was used. After sealing and drying both end faces of the cell, degreasing at about 400 ° C. in an air atmosphere, and then firing at about 1450 ° C. in an Ar inert atmosphere to bond SiC crystal particles with Si. A honeycomb segment having a quality structure was obtained.

(Preparation of bonding material composition)
Under the conditions shown in Table 1, a dispersant, a foamed resin, and an organic binder (CMC) are added to a mixture of filler A and / or filler B, and colloidal silica is further mixed as a matrix and kneaded for 30 minutes with a mixer. Then, paste-like bonding material compositions (bonding material compositions No. 1 to 13) having different types and composition ratios were obtained. The ratio of all fillers in the bonding material composition at this time is the total of filler A and filler B in the “Filler volume fraction in bonding material composition” column of Table 1. For example, the bonding material composition No. In the case of 1, it is 50%, and the ratio of the matrix in the bonding material composition is 100 from the total of filler A and filler B in the “Filler volume fraction in bonding material composition” column of Table 1. Divided. For example, the bonding material composition No. In the case of 1, it is 50%. Moreover, the column of “Others” in Table 1, the dispersant, the foamed resin, and the organic binder were added externally with respect to the total of all fillers and the matrix.

(Preparation of honeycomb structure)
On the outer wall surface of the honeycomb segment, the bonding material composition No. 1 has a thickness of about 1 mm. 1 is coated to form a bonding material layer, and another honeycomb segment is placed thereon, and a honeycomb segment laminated body composed of 16 honeycomb segments combined in 4 × 4 is manufactured. After joining the whole by applying pressure from the outside, it was dried at 140 ° C. for 2 hours to obtain a joined honeycomb segment. The outer periphery of the obtained bonded honeycomb segment assembly was cut into a cylindrical shape, and the outer peripheral surface was applied with a coating material and dried and cured at 700 ° C. for 2 hours to obtain a honeycomb structure.

(Evaluation of bonding material layer (bonding material composition after curing))
The Young's modulus, average thermal expansion coefficient, and porosity of the bonding material portion (cured bonding material composition) in the obtained honeycomb structure were determined by cutting the bonding material portion of the honeycomb structure into a predetermined shape. The Young's modulus was measured from the load-displacement curve in a three-point bending test according to JIS R1601, the average linear thermal expansion coefficient in accordance with JIS R1618, and the porosity was measured by Archimedes method. The results are shown in Table 2.

(Evaluation of honeycomb bonded body)
A bonding state, a rapid heating test (Burner spalling test B-sp), a rapid cooling test (electric furnace spalling test E-sp), and an engine test (E / G test) of the obtained honeycomb structure were respectively performed. The results are shown in Table 2.

(1) Joining state While visually observing the state of the joined part after joining and curing, the joining strength was observed by hand feeling. In addition, in the display of Table 2, in the case of ○, it is a state in which there is no crack or defect in a strong bonding state, and in the case of x, it means a bonding state that is easily peeled or detached, or a state in which there are many cracks or defects. .

(2) “B-sp” test [Burner spalling test (rapid heating test)]
A test that creates a temperature difference between the central part and the outer part by flowing air heated by a burner through the honeycomb structure, and evaluates the thermal shock resistance based on the temperature at which the honeycomb structure does not crack. Is high). In Table 2, the symbol “◯” indicates that no crack is generated, and the symbol “×” indicates that a crack is generated.

(3) “E-sp” test [Electric furnace spalling test (rapid cooling test)]
In this test, the honeycomb structure is heated in an electric furnace at 550 ° C. for 2 hours to obtain a uniform temperature (450 ° C.), taken out to room temperature, and the thermal shock resistance is evaluated based on the presence or absence of cracks in the honeycomb structure. In Table 2, the symbol “◯” indicates that no crack is generated, and the symbol “×” indicates that a crack is generated.

(4) "E / G" test [engine test 1000 ° C]
This test evaluates thermal shock resistance based on the presence or absence of cracks in the honeycomb structure under the condition that the particulates deposited for filter regeneration are burned and the temperature of the honeycomb center stop is 1000 ° C. In Table 2, the symbol “◯” indicates that no crack is generated, and the symbol “×” indicates that a crack is generated.

(Ref Reference Example 2 to 1, Comparative Example 1 and Comparative Example 2)
Reference Examples 2 to 11 are the same as those in Reference Example 1 except that the bonding materials are the bonding material composition Nos. 1 and 2 shown in Table 1. A honeycomb structure was manufactured in the same manner as in Reference Example 1 except that it was changed to 2-11. Moreover, Comparative Example 1 and Comparative Example 2 are bonding material composition Nos. 12 and no. A honeycomb structure was manufactured in the same manner as in Reference Example 1 except that it was changed to 13. The honeycomb structures obtained respectively (Ref Reference Example 2 to 1, Comparative Example 1 and Comparative Example 2) were subjected to the same evaluation and test as in Reference Example 1. The results are shown in Table 2.

(Discussion: ginseng Reference Example 1 to 1 1, Comparative Example 1 and Comparative Example 2)
The results in Table 2, ginseng Reference Example 1 to 1 1, the Young's modulus of the bonding material 20% or more of the objects to be bonded, and, since the average linear thermal expansion coefficient of the bonding material is less than 70% of the object to be bonded After various tests, no cracks were found in the honeycomb structure.

  On the other hand, in Comparative Example 1, the coefficient of linear thermal expansion of the bonding material / the coefficient of linear thermal expansion of the object to be joined was greater than 70%, and therefore cracks occurred after various tests. In Comparative Example 2, since the Young's modulus of the bonding material / Young's modulus of the object to be bonded was less than 20%, the bonding state was poor and a sample to be used for the subsequent tests could not be prepared.

  The bonding material of the present invention can be suitably used for producing a collection filter for exhaust gas, and in particular, a diesel particulate filter (DPF) that collects particulate matter (particulates) and the like in exhaust gas from a diesel engine. .

Claims (7)

Mainly composed of two or more fillers and a matrix of a filler (1) having an average linear thermal expansion coefficient at 25 to 800 ° C. of 50% or less of the article to be joined and a filler (2) having a Young's modulus of 100 GPa or more. Formed by the bonding material composition,
The Young's modulus after curing is 20% or more of the article to be bonded, and the average linear thermal expansion coefficient at 25 to 800 ° C. after curing is 0.1 × 10 ^{−6 to} 2.0 × 10 ⁻⁶ · K ^−1. And 70% or less of the object to be joined,
The material of the object to be bonded is silicon carbide (SiC), silicon carbide (SiC) is formed as a bonding material a and silicon (Si) as aggregate - silicon carbide based composite material, silicofluoride-containing - carbide composites is composed of at least one selected one of Ranaru group,
The volume fraction of the sum of the filler (1) and the filler (2) is equal to the volume fraction of the matrix,
Filler (1) the volume fraction of the sum of said filler (1) and the filler (2): filler (2) = 5 0: 50-9 0: is 10,
The filler (1) is a Kojerai bets,
Wherein the filler (2), silicon carbide, nitride boron, talc, and a mica, and at least one or more selected from the group consisting of glass flakes, and boron nitride is a plate-like particles, talc, mica, and Including at least one selected from the group consisting of glass flakes,
The bonding material, wherein the matrix is at least one selected from the group consisting of colloidal silica, colloidal alumina, ethyl silicate, water glass, silica polymer, aluminum phosphate, and bentonite. 2. The bonding material according to claim 1, wherein the filler (1) has an average linear thermal expansion coefficient at 25 to 800 ° C. of 2.5 × 10 ⁻⁶ · K ⁻¹ or less.   The bonding material according to claim 1, wherein the matrix is colloidal silica.   The bonding material according to claim 1, which is used for bonding honeycomb segments. A method for producing a bonding material for obtaining the bonding material according to claim 1,
The manufacturing method of a joining material including the process of obtaining the paste-like joining material composition by mixing the said filler (1), the said filler (2), and the said matrix, and knead | mixing.   A ceramic structure produced by bonding a plurality of ceramic members with the bonding material according to claim 1.   A honeycomb structure manufactured by bonding a plurality of honeycomb segments with the bonding material according to claim 1.

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